I googled it and it said 50-100 billion
<span>Dmitri Ivanovich Mendeleev</span>
He was a Russian chemist and inventor. He formulated the Periodic Law, created a farsighted version of the periodic table of elements,
and used it to correct the properties of some already discovered
elements and also to predict the properties of eight elements yet to be
discovered.
B) Many Italian city-states of the Renaissance were republics.
Explanation:
Italy was a group or the number of city-states, each of which has its own rule such as the Pope ruling in Rome, the Medici family that is ruling in Florence, the Doge basically ruling in Venice, the Sforza family served for ruling in Milan, the Este family which was ruling in the Ferrara and there is a long list that is consist of all the states of the cities and the ruling families of the ruling people.
The Great Migration was the relocation of more than 6 million African Americans from the rural South to the cities of the North, Midwest and West from about 1916 to 1970.
